  var b64array = "ABCDEFGHIJKLMNOP" +
             "QRSTUVWXYZabcdef" +
             "ghijklmnopqrstuv" +
             "wxyz0123456789+/" +
             "=";
  function encodePlain() {
      input = $("#plain").val();
      var base64 = "";
      var hex = "";
      var chr1, chr2, chr3 = "";
      var enc1, enc2, enc3, enc4 = "";
      var i = 0;

      do {
          chr1 = input.charCodeAt(i++);
          chr2 = input.charCodeAt(i++);
          chr3 = input.charCodeAt(i++);
      
          enc1 = chr1 >> 2;
          enc2 = ((chr1 & 3) << 4) | (chr2 >> 4);
          enc3 = ((chr2 & 15) << 2) | (chr3 >> 6);
          enc4 = chr3 & 63;
      
          if (isNaN(chr2)) {
              enc3 = enc4 = 64;
          } else if (isNaN(chr3)) {
              enc4 = 64;
          }

          base64  = base64  +
              b64array.charAt(enc1) +
              b64array.charAt(enc2) +
              b64array.charAt(enc3) +
              b64array.charAt(enc4);
          chr1 = chr2 = chr3 = "";
          enc1 = enc2 = enc3 = enc4 = "";
      } while (i < input.length);

      $("#base64").val(base64 );

      encodeHex();
      encodeImage();
  }

  function decode64(input) {
      var output = "";
      var hex = "";
      var chr1, chr2, chr3 = "";
      var enc1, enc2, enc3, enc4 = "";
      var i = 0;

      var base64test = /[^A-Za-z0-9\+\/\=]/g;
      if (base64test.exec(input)) {
          alert("There were invalid base64 characters in the input text.\n" +
                "Valid base64 characters are A-Z, a-z, 0-9, '+', '/',and '='\n" +
                "Expect errors in decoding.");
      }
      input = input.replace(/[^A-Za-z0-9\+\/\=]/g, "");

      do {
          enc1 = b64array.indexOf(input.charAt(i++));
          enc2 = b64array.indexOf(input.charAt(i++));
          enc3 = b64array.indexOf(input.charAt(i++));
          enc4 = b64array.indexOf(input.charAt(i++));
          
          chr1 = (enc1 << 2) | (enc2 >> 4);
          chr2 = ((enc2 & 15) << 4) | (enc3 >> 2);
          chr3 = ((enc3 & 3) << 6) | enc4;
          
          output = output + String.fromCharCode(chr1);
          
          if (enc3 != 64) {
              output = output + String.fromCharCode(chr2);
          }
          if (enc4 != 64) {
              output = output + String.fromCharCode(chr3);
          }
      
          chr1 = chr2 = chr3 = "";
          enc1 = enc2 = enc3 = enc4 = "";
      
      } while (i < input.length);

      return output;
  }
